题目描述

PDF

输入格式

Please view in PDF

输出格式

Please view in PDF

样例

10 9 
1 2 
1 3 
1 4 
1 5 
1 6 
1 7 
1 8 
1 9 
1 10 
10 4 
2 3 
4 5 
4 8 
5 8 
0 0 
Sam

Case 1: 1 
Case 2: 7

提示

Source link

Transcribed by jifengzhiyin